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A short review of pyroducts (lava tubes)

Sawłowicz Zbigniew

Annales Societatis Geologorum Poloniae

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2020

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Vol. 90, No. 4

513--534

EN

Lava tubes and caves, when accessible for man, are very common in volcanic environments and poorly known to non-specialists. This short overview presents the distribution and forms of lava tubes, their speleothems and mineralogy and modes of formation. Studies of lava caves outside of Earth currently are a topic of great interest, as they may be potential locations for some life forms and future bases in space exploration. Basic features of lava tubes are illustrated with reference to the longest lava cave in the world, Kazumura Cave, in Hawaii.

2

Low to middle Pleistocene paleoclimatic record from the Kraków-Częstochowa Upland (Poland) based on isotopic and calcite fabrics analyses

Błaszczyk M., Hercman H., Pawlak J., Gąsiorowski M., Matoušková Š., Aninowska M., Kicińska D., Tyc A.

Geochronometria

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2018

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Vol. 45, no. 1

185--197

EN

The quality of paleoenvironmental reconstruction based on speleothem records depends on the accuracy of the used proxies and the chronology of the studied record. As far as the dating method is concerned, in most cases, the best solution is the use of the U-series method to obtain a precise chronology. However, for older periods (i.e., over 0.5 Ma), dating has become a serious challenge. Theoretically, older materials could be dated with the U-Pb dating method. However, that method requires a relatively high uranium content (minimum of several ppm), whereas typical speleothems from Poland (and all of Central Europe) have uranium concentrations below 0.1 ppm. Because the materials in Polish caves are problematic, we applied oxygen isotope stratigraphy (OIS) as a tool for speleothem dating. By using OIS as an alternative tool to create a chronology of our flowstone, it was found that the studied flowstone crystallized from 975 to 470 ka with three major discontinuities, so obtained isotopic record can be correlated with oxygen isotopic stages from MIS 24 to MIS 12. The observed isotopic variability was also consistent and confirmed with the petrographic observations of the flowstone.

3

New data on pre-Eocene karst in the Tatra Mountains, Central Carpathians, Poland

Gradziński M., Jach R., Hercman H.

Geological Quarterly

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2016

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Vol. 60, No. 2

291-300

EN

Sparry limestone, ferruginous muddy limestone and limestone breccia have been found in the Western Tatra Mts. They occur within Jurassic rocks of the Choč Nappe just below red conglomerates of probable Eocene age. The deposits found bear strong resemblance to the infill of subterranean karst forms. They differ significantly from Quaternary karst deposits of the Tatra Mts. The δ18O values of spelean carbonates suggest crystallisation at relatively high temperatures (over 20°C) whereas their relatively negative δ13C values imply the presence of soil-derived CO2 linked with vegetation dominated by C3 pathway plants. The karst forms and their infill were formed before the Eocene transgression, which shows unequivocally that the Tatra Mts. were subjected to karstification at that time.

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Transmission electron microscopy (TEM) as a tool for identification of combustion products : application to black layers in speleothems

Pawlyta M., Hercman H.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 2

237--248

EN

The present study deals with the application of High Resolution Transmission Electron Microscopy (HRTEM) to dark layers, occurring in the speleothems of Domica Cave (Slovakia). Chemical pre-treatment was necessary for sample purification and the effective extraction of carbon soot. For purposes of comparison, soot aggregates obtained from laboratory experiments on the combustion of beech wood and collected from a diesel engine also were studied. HRTEM analyses of combustion products permit a distinction to be made between soot aggregates that originated in different combustion processes. The diameter of spherical, primary particles depends on the conditions of combustion, notably temperature. Burning in diesel engines produces soot with relatively small, primary particles (diameter dp = 34 ± 4 nm). Primary, spherical particles of soot aggregates, obtained from the combustion of beech wood, were larger (diameter dp = 42 ± 5 nm). The diameters of primary particles of soot separated from Domica flowstones (samples DOM1 and DOM2) were similar to the wood samples (dp = 50 ± 9 nm). Another type of carbonaceous particle, obtained in the combustion process, had a spherical shape, but the diameter of about 50–500 nm was significantly larger than that of soot. Analyses performed on two samples (DOM S1 and DOM S2) confirmed that the black laminae owed their colour to particles, formed during wood combustion and later retained in the speleothems.

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New isotopic data on karst development in the northern Kraków-Wieluń Upland (southern Poland)

Hercman H., Gąiorowski M., Sujka G.

Annales Societatis Geologorum Poloniae

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2016

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Vol. 86, No. 4

429--436

EN

The Kraków-Wieluñ Upland is one of the major palaeokarst regions in Poland. However, the stages of karst development in this area are neither well documented nor reconstructed. A series of samples from a new location in the vicinity of Raciszyn was analysed. On the basis of the results of U-series dating, four phases of speleothem deposition were distinguished: (1) older than 600 ka, (2) from more than 600 ka to 290 ka, (3) around 150 ka, and the youngest (4), younger than 3 ka. On the basis of all geochronological data from the region, eight stages of karst development were described. The structure of the oldest speleothems indicates even more stages of deposition and erosion that cannot be recognized using the 230Th/234U dating method. These results indicate that the initial creation of empty spaces in the limestone took place in pre-Pleistocene time. After 600 ka ago, climatic conditions were stable for more than 300 ka, allowing the continuous deposition of speleothems. Several episodes of erosion, deposition of clastic sediments and speleothem growth during the Middle and Early Pleistocene were described. This variability of the sedimentation regime clearly reflects climate changes during that period.

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Pleistocene speleothem fracturing in the Western Carpathian orogenic foreland : A case study from transtensional setting at the eastern margin of the Bohemian Massif

Babek O., Briestenský M., Přecechtělová G., Štěpančíková P., Hellstrom J. C., Drysdale R. N.

Geological Quarterly

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2015

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Vol. 59, No. 3

491–-506

EN

We studied speleothem-fracturing styles and their tectonic context in three cave systems situated in the eastern Bohemian Massif, close to the Western Carpathians orogenic front: the Za hájovnou, Javoříčko, and Mladeč caves. The morphology of the speleothems in particularly thin stalactites, and supporting evidence from the cave interior, indicates a tectonic origin of the breakage. U/Th series dating of the stalactites, supported by Optically Stimulated Luminiscence (OSL) and 14C dating of soft sediments indicate that most of the fracturing occurred in the Upper Pleistocene, with the last fracturing events corresponding to MIS6 and MIS5 stages. OSL dating of faulted soft-sediment infill may even indicate that latest Pleistocene to Early Holocene tectonic events occurred in the Mladeč Cave. The speleothem fracturing is discussed in the regional context of the seismically active Nysa-Morava Zone situated at the junction between the Bohemian Massif (Elbe Fault Zone) and the Western Carpathians. This study provides the first evidence of palaeoseismicity from the subsurface and the oldest dated palaeoseismicity from the contact between the Western Carpathians and the Bohemian Massif.

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Drip rate and tritium activity in the Niedźwiedzia Cave system (Poland) as a tool for tracking water circulation paths and time in karstic systems

Gąsiorowski M., Hercman H., Pruszczyńska A., Błaszczyk M.

Geochronometria

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2015

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Vol. 42, no.1

210--216

EN

The Niedźwiedzia Cave system is composed of 3 horizontal levels of passages and chambers. Changes in the drip rate of water from the upper level stalactites correlate well with changes in precipitation intensity. The transition time between the surface and the upper level of the cave was estimated to 14 days. Drip sites in the middle and lower levels of the cave exhibited two types of recharge: some did not correlate with precipitation intensity, whereas others correlated well with rain events. The transition times for the latter sites were estimated to be greater than 6 months. This estimate was confirmed by the calculation of the transition time based on tritium activity. The oldest water in the entire karst system was observed in a karst spring. The mean tritium age for this water during winter was estimated to be 3.9 ± 0.6 yr. More precise calculations of the tritium age of karst water require longer precipitation activity datasets.

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Needle-fibre calcite and nanofibres as components of Holocene fissure-filling carbonates in southern Poland

Gradziński M., Jach R., Górnikiewcz R.

Annales Societatis Geologorum Poloniae

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2013

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Vol. 83, No. 3

229–242

EN

The article deals with the carbonates, filling fissures in limestone bedrock and presently exposed in a south-facing rock wall of Kramnica hill (Pieniny Klippen Belt, southern Poland). The carbonates are composed of (i) needle-fibre calcite crystals, (ii) carbonate nanofibres, (iii) carbonate nanoparticles, and (iv) micrite and sparite calcite crystals. Detrital grains from the carbonate bedrock occur subordinately. The spatial relationships of the components give documentation that the nanofibres were formed simultaneously with or slightly later than the needle-fibre calcite crystals. There exists a continuous chain of forms from nanoparticles to elongated nanofibres. This, in turn, indicates that all the above morphological forms are related genetically. In relatively wide fissures, the carbonates studied formed stepped microterracettes, similar to those of speleothems, mainly of moonmilk type. Conversely, narrow fissures are completely filled with carbonates, which display parallel lamination. The carbonates were formed in the late Holocene. However, “dead carbon effect” precludes the possibility of any precise dating of them. Their δ13C and δ18O values are in ranges from -5.1‰ to -3.8‰ and from -6‰ to -4.7‰, respectively. The carbonates studied bear a strong resemblance to soil and spelean, moonmilk-type carbonates. This indicates that continuity exists between the depositional environments of soil and spelean carbonate.

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Peculiar calcite speleothems filling fissures in calcareous sandstones and their palaeohydrological and palaeoclimatic significance: an example from the Polish Carpathians

Gradziński M., Duliński M., Hercman H., Górny A., Przybyszowski S.

Geological Quarterly

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2012

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Vol. 56, No. 4

711--732

EN

Peculiar calcite speleothems developed in fissures in the Cergowa Sandstones were found in the Klęczany Quarry (Polish Western Carpathians). They represent flowstone and stalactites, rafts and various sparry crusts. Such speleothems, especially phreatic ones, are uncommon in the Outer Carpathians that are composed mainly of siliciclastic rocks of flysch type, with only limited calcium carbonate content. The speleothems analysed grew in vadose and phreatic conditions as well as at the air-water interface. Phreatic speleothems and thin rafts comprise calcite crystals of eccentric morphology. Based on their stable isotope composition the majority of the speleothems form two clusters. The first is characterized by d18O values between –9.8 and –8.5‰ and of d13C values between –5.7 and –0.6‰ whereas the second cluster of samples yields d18O values between –9.4 and –7.3‰ and d13C values from –11.5 to –9.7‰. Speleothems grew between 230+14–13 ka and Holocene time. Phreatic speleothems, including massive rafts, precipitated from ascending water of deep circulation whereas vadose and water table speleothems crystallized from local infiltration water charged with soil CO2. Mixing of both waters in the shallow phreatic zone is plausible.

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Formation of calcite by chemolithoautotrophic bacteria – a new hypothesis, based on microcrystalline cave pisoids

Gradziński M., Chmiel M.J., Motyka J.

Annales Societatis Geologorum Poloniae

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2012

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Vol. 82, No. 4

361–-369

EN

A new mechanism, stimulating the precipitation of calcite, is postulated. The supersaturation with respect to carbonate minerals is changed, as a result of CO2consumption by chemolithoautotrophic, hydrogen-oxidizing bacteria. This mechanism controls the growth of atypical, microcrystalline cave pisoids in Perlová Cave, in Slovakia. The pisoids grow under calm conditions in rimstone pools, where they are bathed continuously in stagnant water. The water is supersaturated, with respect to calcite and aragonite. The bacteria inhabit the outer parts of the pisoids, covered by biofilms. The biofilm influences the supply of the Ca2+ ion, slows down the precipitation rate, and favors calcite precipitation over that of aragonite. The calcite initially precipitates as bacterial replicas, which further act as seeds for the growing calcite crystals. This process leads to the obliteration of the primary, bacterial fabrics. Since hydrogen-oxidizing bacteria occur in a wide spectrum of natural habitats, the mechanism of calcification, postulated above, also may operate in other environments.

11

Siliciclastic micro- stromatolites in a sandstone cave: role of trapping and binding of detrital particles in formation of cave deposits

Gradziński M., Chmiel M. J., Lewandowska A., Michalska-Kasperkiewicz B.

Annales Societatis Geologorum Poloniae

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2010

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Vol. 80, No 3

303-314

EN

The article deals with finely laminated microstromatolites composed of detrital siliciclastic particles, mainly quartz, feldspars and clay minerals, lining the walls of W Sopotni Wielkiej Cave (Polish Outer Carpa- thians). Newly precipitated mineral phases do not contribute to their growth. The microstromatolites cover vertical and overhanging walls of the cave. They form subhorizontal ripples and tongue-shaped stepped microterracettes. The stromatolites are constructed by bacteria and Actinomycetes. Seven morphotypes of micro-organisms have been distinguished. Trapping and binding of detrital particles result in the microstromatolite growth. The growth is influenced by the relatively close distance to the soil cover which provides detrital mineral particles and by the presence of gravitationally widened fissures which guide the water transporting mineral particles down to the cave. The particles are transported only during wet periods. The episodic supply of the particles results in visible lamination of microstromatolites. The microterracettes form in zones of increased water-flow. The lack of auto- chthonous components most probably reflects too low saturation of water to precipitate any minerals.

12

Kras tatrzański - rozwój wiedzy w ostatnich trzydziestu latach

Gradziński M., Hercman H., Kicińska D., Barczyk G., Bella P., Holúbek P.

Przegląd Geologiczny

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2009

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Vol. 57, nr 8

674-684

EN

The paper presents the latest results of studies on karst phenomena in the Tatra Mountains. Three periods of pre-Neogene karstification have been identified, that is Middle to Late Triassic, Albian and Palaeocene to Early Eocene. Up to now, 1168 caves have been registered in the Tatra Mts: 805 in Poland and 363 in Slovakia. Their total length exceeds 175 km. Wielka Śnieżna Cave from Mt. Małołączniak (Czerwone Wierchy Massif), with its total length of more than 23 km and vertical extent 824 m, is the deepest and longest of those hitherto found in this region. In the recent years the idea on hydrothermal origin of a number of caves in this area has been put forward. Other caves formed under phreatic conditions display numerous phreatic loops. Therefore, spatial distribution of these caves does not mark the former position of a water-table. The direction of palaeoflow was generally similar to that of the modern karst drainage. The U-series dating of speleothems has revealed that the phreatic stage in development of some caves ended earlier than 1.2 Ma. The mean rate of valley deepening during the last 200 ka was estimated at 0.2-0.3 m/ka. The microbial origin of moonmilk deposits, which are very common in the Tatra caves, has been put forward. The analyses of speleothem isotopic composition show that not only temperature but also migration path of feeding water can govern the delta exp.18 values. The palaeontological and archaeological findings in the Tatra caves are scarce. Presently, the cave lion bones and sculls accompanied by numerous bones of a cave bear were found in a Slovak cave (Medvedia jaskyňa). Dye-tracing tests, both in Polish and Slovak parts of the mountains, have been conducted to confirm connections between particular sink-holes and karst springs. The stable isotopic composition of karst-spring water and water residence time based on tritium content have been studied as well.

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Evolution of Brestovská Cave based on U-series dating of speleothems

Hercman H., Gradziński M., Bella P.

Geochronometria

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2008

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Vol. 32

1-12

EN

The U-series dating indicates five episodes of flowstone growth in Brestovská Cave, namely: ca. 200 ka, ca. 128-88 ka, ca. 82-65 ka, ca. 64-50 ka, and during the Holocene. The age of flowstones and their spatial distribution within the cave prove that the upper storey of the cave was dewatered before 200 ka. At that time the lower storey also existed and was able to carry the whole water flowing through the cave. It suggests that 200 ka ago the water-table was at similar level as it is at present. Hence, one should accept that the valley bottom was then also at the present level. During at least a part of the MIS 6 the growth of speleothems was possible in the cave. It suggests that the cave was located outside the permafrost zone then. Between 50 ka and Holocene, Brestovská Cave was flooded by invasion waters originating from the melting of the Würm glacier; the water-table was additionally raised due to the blockage of a resurgence by glacifluvial sediments. The flooding event caused the destruction of older deposits, including speleothems, and deposition of fine-grained clastics on the cave walls.

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Oświetlenie elektryczne zmienia szatę naciekową w jaskiniach

Różowicz A.

Nowa Elektrotechnika

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2006

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nr 10 (26)

10--12

15

Uranium-series and radiocarbon dating of speleothems - methods and limitations

Hercman H., Goslar T.

Acta Geologica Polonica

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2002

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Vol. 52, nr 1

35-41

EN

^14C ages of speleothems are usually younger than the Uranium-Series ages. The difference is often explained by changes of atmospheric radiocarbon concentration in the past, and in fact, speleothems have been as a material for radiocarbon time scale calibration. However in other works large spread of data points has been obtained. Comparison with the ^14C calibration data suggests that many ^14C of speleothems ages are too young or the Uranium-Series ages too old. ^14C dates of speleothems are commonly treated with caution, because of the reservoir effect, producing an apparent age, which is usually not accurately known. However, the reservoir effect may be of minor importance when compared to contamination with younger carbon.

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New speleothem dates from caves in Germany and their importance for the Middle and Upper Pleistocene climate reconstruction

Kempe S., Rosendahl W., Wiegand B., Eisenhauer A.

Acta Geologica Polonica

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2002

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Vol. 52, nr 1

55-61

EN

Twenty speleothems from caves of different karst regions (mainly from the Franconian-Swabian Alb and the Bavarian Alps) in Germany were dated with the TIMS-U/Th-method. The samples were taken from stalagmites of various sizes. Beginning and end of the growth phases were determined by dating the base and the tip of each sample. The dates obtained fit into the general scheme of Pleistocene climate in Germany, where speleothem growth is interrupted by cold periods. Some of the samples could not be dated because they suffered from secondary loss of uranium most probably due to leaching. Those samples belong to visibly older sinter generations. Leaching could have occuredunder permafrost conditions when the caves were filled with ice or when groundwater was trapped in the caves below a permafrost cover.

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Reconstruction of palaeoclimatic changes in Central Europe between 10 and 200 thousand years BP, based on analysis of growth frequency of speleothems

Hercman H.

Studia Quaternaria

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2000

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Vol. 17

35-70

EN

The present study is an attempt to utilise the uranium-thorium dates of speleothems as a source of palaeoclimatic data. The clue is that the changing climate influenced intensity of speleothem deposition, which is reflected in clustering of USeries dates of speleothems in certain time intervals. This work discusses and improves various methods of com bined presentation of dates, with a special attention to the presentation in form of growth frequency (`pdf') curves. Using the `bootstrap' method the confidence intervals of the `pdf' curves could be determined. Also the algorithm, originally developed to determine parameters of arbitrarily chosen maxima in the curve, has been modified. Due to that an assessment of number of maxima has been possible. This method enables objective distinction of phases of speleothem growth, which cannot be done `by eye' when the `pdf' curve is smooth. The statistical tests show that the reliable `pdf'curve should contain more than 150 dates. Basing on 308 Useries dates of cave speleothems from southern Poland and other regions of central Europe, the growth frequency curves for the Carpathians and Uplands have been constructed. Comparison of phases of speleothem growth, distinguished by various authors for several regions of Europe, indicates that the climatic changes were syn chronous over the whole region. However, different shapes of the `pdf' curves reflect increasing continuity of speleo them growth in the N-S transect southwards. This may be connected with the N-S climatic gradient in Europe. Using the `pdf' curves from caves of Tatra and Low Tatra Mountains the most probable timing of development phases of mountain glaciers has been delimited.